H-3342 – Xylem H-3342 User Manual
Page 27

H-3342
SDI-12 Command and Response Protocol 3-15
3.15 Extended Read Power_Mode and Write Power_Mode
The 4-20mA output is updated whenever a measurement is made. For industrial applications
where the H-3342 is connected to a SCADA or PLC system and low-power is not of concern, the
H-3342 can be programmed to make continuous measurements. This command is used to change
the power mode. The H-3342 comes from the factory with the power mode set to the Sleep mode.
Once a new value is written, a copy is sent to the sensor data buffer for verification. This data
can be viewed by using a subsequent "D" command. To read or verify the value any other time,
use the "XRPMD" command.
Command
Response
Description
"aXRPMD!"
“a0011
Read Power_Mode
"aXWPMDn!"
“a0011
Write Power_Mode
Where:
a
is the sensor address ("0-9", "A-Z", "a-z", "*", "?").
XRPMD
are upper case characters.
XWPMD
are upper case characters.
n
is the new setting (0 or 1)
0 = Sleep between measurements
1 = Make continuous measurements (always on)
This command takes 001 seconds to complete and places 1 value in the data buffer. Use the
“aD0" command to collect and view the current value.
Example of a H-3342 Extended "Read Power_Mode" command:
Command
Response
Time
Values
Description
"aXRPMD!"
"a0011
1 sec
1
Read Power_Mode
Command
Response
Description
"aD0!"
"a+0
Mode = Sleep
Example of a H-3342 Extended "Write Power_Mode" command:
Command
Response
Time
Values
Description
"aXWPMD1!"
"a0011
1 sec
1
Write Power_Mode
Command
Response
Description
"aD0!"
"a+1
Mode = Always On